1. Field of the Invention
The invention is generally related to the area of man machine interface. In particular, the invention is related to method and apparatus for effectively scrolling through a large list of items.
2. The Background of Related Art
The most popular use of a scroll wheel may be probably found on an Apple's iPod. A scroll wheel of an iPod allows a user to scroll where he/she desires. Thus a user can choose songs to play on from lists of artists, albums, composers, genres, or tracks.
The underlying mechanism of a scroll wheel is a software module being executed to convert a physical motion of the user moving his/her finger over the scroll wheel to a highlight bar on a list of music items. The software module is configured based on the concept of ‘acceleration’. In simple terms, this means that the faster the user turns the scroll wheel, the faster the list on the screen will scroll. This is very effective in allowing users to traverse long lists.
There are, however, at least two problems observed. First, it still takes a long time to get through a large list of music items. For example, if a desired item is an item No. 1500 in a list of 2000 songs, a user has to go through the first 1499 items before reaching the item No. 1500. Second, when a list is scrolled fast, it is very hard for the user to stop at the desired position without overshooting. For example. If the list is showing an artist named “Abba”, and the user wants to scroll to an artist named “Sting”, he/she must turn the scroll wheel fast in order to get from Abba to S's quickly. But because the list is long and so being scrolled fast, it is very easy to overshoot the list and get to the T's or U's by moving his/her finger on the scroll wheel too fast.
It is commonly accepted that a scroll wheel is a convenient mechanism to scroll through a list. Thus, there is a need for solutions that can facilitate a user to readily reach to a desired item in a long list.